What is Sorbitol Dehydrogenase (SORD) Deficiency?

Sorbitol Dehydrogenase (SORD) Deficiency is a recently discovered rare, genetic metabolic disease. 

People with SORD Deficiency are missing a key enzyme needed to metabolize a sugar called sorbitol.

Before the discovery of the SORD gene, patients with SORD Deficiency were diagnosed based on their symptoms as having Charcot-Marie-Tooth disease (CMT2) or distal hereditary motor neuropathy (dHMN). The recent discovery that disease symptoms in CMT2 and dHMN can be caused by genetic mutations in the SORD enzyme, now gives people living with SORD Deficiency, and their physicians, greater understanding of their specific disease.  It also provides the opportunity to participate in a clinical trial of an investigational new treatment targeting the underlying cause of SORD Deficiency.

How many people have SORD Deficiency?

SORD Deficiency is a rare disease that impacts 1 in every 100,000 people.  In the US, it is estimated that there are only 3,300 individuals living with the disease.

SORD Deficiency is a form of hereditary neuropathy, which means that this disease was passed down from both parents’ genes.  Not all people with SORD Deficiency have a family history of hereditary neuropathy.

What happens in the body of someone living with SORD Deficiency?

Glucose is a simple sugar that the body converts into fructose for energy.  One of the ways the body breaks down glucose is through a two-step metabolic pathway.

In this metabolic pathway, two enzymes work to process glucose and then sorbitol.

1. In the first step, the enzyme Aldose Reductase metabolizes glucose into sorbitol
2. In the second step, the enzyme Sorbitol Dehydrogenase (SORD) converts sorbitol into fructose